Preparation method of monodisperse cadmium phosphide semiconductor nanoparticles with free size adjustment, and product and application thereof

Abstract

This invention discloses a method for preparing monodisperse cadmium phosphide semiconductor nanoparticles with freely adjustable size, as well as the product and applications thereof. The invention uses cadmium oxide and oleic acid as raw materials, and octadecene as a medium. Under controlled reaction temperature, trimethylsilphosphine is added for phosphating reduction treatment, ultimately yielding monodisperse cadmium phosphide particles with freely adjustable size. The advantages of this preparation method are its ability to effectively control the size of the monodisperse cadmium phosphide particles; different amounts of trimethylsilphosphine added result in different particle sizes. This material can significantly improve photocatalytic performance, especially the degradation rate of tetracycline wastewater. The preparation method is simple and low-cost, representing a highly promising approach for preparing cadmium phosphide semiconductor particles.

Description

Technical Field

[0001] This invention belongs to the technical field of functional material preparation, specifically relating to a method for preparing monodisperse cadmium phosphide semiconductor nanoparticles with freely adjustable size, as well as its products and applications. Background Technology

[0002] Cadmium phosphide is a representative type II-V semiconductor functional material with a band gap of 0.55 eV. It possesses tunable optical and photoelectric properties, showing great promise for applications in infrared detectors, ultrasonic multipliers, and solar cells. Furthermore, it can fully absorb visible light and generate free radicals with strong oxidizing power. Its stable photochemical properties and environmental friendliness also make it a promising candidate for photocatalytic water splitting, pollutant degradation, and antibacterial applications. Traditional methods for preparing nano-cadmium phosphide include physical and chemical methods. Physical methods can yield high-purity nano-cadmium phosphide powder, but suffer from high production costs, large investment, low yield, and difficulty in industrialization. Chemical methods are commonly used for preparing nano-cadmium phosphide. This method involves reducing metal ions to elemental cadmium phosphide with yellow phosphorus in a solvent or aqueous solution under the coating of a surfactant. Nano-cadmium phosphide prepared using this method exhibits good stability, but the yield is low, the process is complex and difficult to control, and industrial production faces certain challenges.

[0003] Chinese invention patent application CN201610952852.X disclosed a method for preparing nano-cadmium phosphide. This method uses cadmium chloride and yellow phosphorus as raw materials, adds a certain amount of ethylenediamine, and performs a solution-liquid phase reduction reaction to prepare cadmium phosphide sol. Then, the cadmium phosphide particles are further matured using a microwave hydrothermal method. After the reaction, the solid phase is washed and dried to finally obtain cadmium phosphide nanoparticles. Although this method can obtain cadmium phosphide nanoparticles, the size of these nanoparticles is generally around 10 nm, and the size cannot be controlled. How to prepare cadmium phosphide nanoparticles with freely adjustable size remains a challenge.

[0004] This patent application discloses a method for preparing cadmium phosphide particles with freely adjustable particle size and its application. This method abandons the conventional solvothermal method, uses cadmium oxide and octadecene as raw materials, and trimethylsilylphosphide as a size regulator. Monodisperse cadmium phosphide particles are prepared by a simple liquid-phase reaction. This method realizes the free control of cadmium phosphide size and has the characteristics of simple process, short production cycle, energy saving and environmental protection. It is a preparation method with great development prospects. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing monodisperse cadmium phosphide semiconductor nanoparticles with freely adjustable particle size.

[0006] Another objective of this invention is to provide a monodisperse cadmium phosphide semiconductor nanoparticle product with freely adjustable particle size prepared by the above method.

[0007] Another object of the present invention is to provide an application of the above-mentioned product.

[0008] The objective of this invention is achieved through the following solution: a method for preparing and applying monodisperse cadmium phosphide semiconductor nanoparticles with freely adjustable size. This invention is achieved through the following technical solution: a method for preparing and applying monodisperse cadmium phosphide semiconductor nanoparticles with freely adjustable size, characterized by using cadmium oxide and oleic acid as raw materials, octadecene as a medium, and adding trimethylsilphosphine for phosphating reduction treatment under controlled reaction temperature, ultimately obtaining monodisperse cadmium phosphide particles with freely adjustable size. The specific steps are as follows:

[0009] Cadmium oxide, oleic acid, and octadecene were accurately weighed according to specific proportions and uniformly mixed in a three-necked flask. Stirring was initiated, and argon gas was introduced into the flask as a protective gas to purge any interfering gases. The flask was then sealed, heated, and maintained at a specific temperature. Trimethylphosphine was then injected into the reaction solution at this temperature in a specific proportion and maintained at this temperature for 10 minutes. The flask was cooled to room temperature, and the solid-liquid reaction product was poured out. The product was centrifuged, washed successively with chloroform and cyclohexane, and finally dried to obtain monodisperse cadmium phosphide semiconductor nanoparticles.

[0010] The mass ratio of cadmium oxide, oleic acid, and octadecene is 1.5:1:(200~400).

[0011] The heating temperature of the three-necked flask is controlled at 250°C.

[0012] The mass ratio of the added trimethylsilphosphine to cadmium oxide is controlled to be (2~1):1;

[0013] This invention provides monodisperse cadmium phosphide semiconductor nanoparticles with freely adjustable size, prepared according to any of the methods described above.

[0014] This invention provides an application of monodisperse cadmium phosphide semiconductor nanoparticles with freely adjustable size in the efficient catalytic degradation of tetracycline in dye wastewater.

[0015] The technical principle of this invention is that, using the above-described preparation process, after mixing cadmium oxide, oleic acid, and octadecene, Cd... 3+Ions dispersed in an octadecene medium generate cadmium oleate monomers due to the presence of oleic acid. These monomers exhibit high activity at higher temperatures and undergo a complete reduction reaction with added trimethylsilylphosphine to obtain monodisperse cadmium phosphide microcrystals. These microcrystals then rapidly incubate and grow to yield cadmium phosphide nanocrystals with adjustable particle size. The amount of trimethylsilylphosphine added dominates the entire growth process of cadmium phosphide, resulting in cadmium phosphide semiconductor nanoparticles with varying sizes.

[0016] The advantage of this invention is that it eliminates the hydrothermal or solvent-based reaction methods used in traditional chemical synthesis, instead employing a liquid-phase reduction method to self-assemble cadmium phosphide semiconductor nanoparticles with tunable size. Preliminary performance tests show that this material exhibits excellent photocatalytic decomposition performance in pharmaceutical wastewater. Therefore, this material has promising development and application prospects.

[0017] This method uses cadmium oxide and oleic acid as raw materials and octadecene as the reaction medium. Under controlled reaction temperature, trimethylsilphosphine is added for phosphating reduction treatment, ultimately yielding cadmium phosphide particles with freely adjustable size. The particle size varies with the amount of trimethylsilphosphine added. This material has shown high photocatalytic activity in the degradation reaction of pharmaceutical wastewater. Attached Figure Description

[0018] Figure 1 This is a transmission electron microscope image of the monodisperse cadmium phosphide semiconductor nanoparticles obtained in Example 1.

[0019] Figure 2 The image shows the photocatalytic performance spectrum of cadmium phosphide semiconductor nanoparticles obtained in Example 1 as a catalyst. Detailed Implementation

[0020] This embodiment is implemented based on the technical solution of the present invention, and provides detailed implementation methods and specific operation processes. However, the scope of protection of the present invention is not limited to the following embodiment.

[0021] Example 1

[0022] A monodisperse cadmium phosphide semiconductor nanoparticle with freely adjustable size was prepared by using cadmium oxide and oleic acid as raw materials, octadecene as a medium, and adding trimethylsilphosphine for phosphating reduction treatment under controlled reaction temperature, ultimately yielding a monodisperse cadmium phosphide particle with freely adjustable size. The preparation steps are as follows:

[0023] Accurately weigh 0.7g of cadmium oxide, 0.48g of oleic acid, and 144g of octadecene into a three-necked flask, mix thoroughly, and start stirring; then,

[0024] Argon gas was introduced into the three-necked flask as a protective gas to eliminate interfering gases inside the flask; then...

[0025] Seal the three-necked flask, heat it to 250°C and maintain that temperature; then...

[0026] 1.4 g of trimethylsilphosphine was injected into the reaction solution and kept at this temperature for 10 min;

[0027] Cool the three-necked flask to room temperature naturally, and pour out the solid-liquid reaction products from the flask.

[0028] Centrifugation was performed, followed by washing with chloroform and cyclohexane, and finally drying at 60°C for 8 hours to obtain a dry powder, which is monodisperse cadmium phosphide semiconductor nanoparticles.

[0029] Figure 1 This is a transmission electron microscope (TEM) image of the cadmium phosphide semiconductor nanoparticles obtained in Example 1. Figure 1 It is evident that the material consists of monodisperse nanoparticles with a particle size of only 5 nm, belonging to the nanocrystal series.

[0030] Photocatalytic performance testing of cadmium phosphide materials:

[0031] Using tetracycline aqueous solution as an organic pollutant in wastewater, the catalytic effect of the photocatalyst in this invention under simulated sunlight was verified.

[0032] The method is as follows: 50 mg of photocatalyst is placed in 80 mL of 100 mg / L tetracycline aqueous solution and placed in the dark for 30 min until adsorption equilibrium is reached. After adsorption is completed, photocatalytic reaction is carried out under 500 W xenon lamp irradiation. During the photocatalytic process, 5 mL of tetracycline solution is taken as a sample every 10 min. The absorbance of tetracycline solution at different catalytic times is measured by spectrophotometer and converted into concentration to characterize the degradation effect.

[0033] Figure 2 This is the photocatalytic performance spectrum of the cadmium phosphide material obtained in Example 1. Comparison with the blank test (see...). Figure 2 As shown in the figure, the cadmium phosphide material prepared by this invention has a highly efficient catalytic degradation effect on tetracycline.

[0034] Example 2

[0035] A monodisperse cadmium phosphide semiconductor nanoparticle with freely adjustable size is prepared according to a procedure similar to that in Example 1, as follows:

[0036] Accurately weigh 0.7g of cadmium oxide, 0.48g of oleic acid, and 144g of octadecene into a three-necked flask, mix thoroughly, and start stirring; then,

[0037] Argon gas was introduced into the three-necked flask as a protective gas to eliminate interfering gases inside the flask; then

[0038] Seal the three-necked flask, heat it to 250°C and maintain that temperature; then...

[0039] 0.7 g of trimethylsilphosphine was injected into the reaction solution and kept at this temperature for 10 min;

[0040] Cool the three-necked flask to room temperature naturally, and pour out the solid-liquid reaction products from the flask.

[0041] Centrifugation was performed, followed by washing with chloroform and cyclohexane, and finally drying at 60 °C for 8 h to obtain a dry powder, which is monodisperse cadmium phosphide semiconductor nanoparticles.

[0042] The size of the monodisperse cadmium phosphide semiconductor nanoparticles was determined to be 2.5 nm, and they exhibited highly efficient catalytic effect on tetracycline when used as a photocatalyst.

[0043] Example 3

[0044] A monodisperse cadmium phosphide semiconductor nanoparticle with freely adjustable size is prepared according to a procedure similar to that in Example 1, as follows:

[0045] Accurately weigh cadmium oxide, oleic acid, and octadecene at a mass ratio of 1.5:1:(200~400), mix them evenly in a three-necked flask, start stirring, and then introduce argon gas into the three-necked flask as a protective gas to eliminate interference from oxidizing gases. Next, seal the three-necked flask, heat it to 250°C, and inject trimethylsilphosphine into the reaction solution at this temperature. The mass ratio of trimethylsilphosphine to cadmium oxide is controlled at (2~1):1, and this temperature is maintained for 10 min. Cool the three-necked flask to room temperature, pour out the solid-liquid reaction product from the flask, centrifuge, wash with chloroform and cyclohexane successively, and finally dry the powder to obtain monodisperse cadmium phosphide semiconductor nanoparticles.

[0046] Accurately weigh 0.7g of cadmium oxide, 0.48g of oleic acid, and 144g of octadecene into a three-necked flask, mix thoroughly, and start stirring; then...

[0047] Argon gas was introduced into the three-necked flask as a protective gas to eliminate interfering gases inside the flask; then

[0048] Seal the three-necked flask, heat it to 250°C and maintain that temperature; then...

[0049] 1.0 g of trimethylsilphosphine was injected into the reaction solution and kept at this temperature for 10 min;

[0050] Cool the three-necked flask to room temperature naturally, and pour out the solid-liquid reaction products from the flask.

[0051] Centrifugation was performed, followed by washing with chloroform and cyclohexane, and finally drying at 60 °C for 8 h to obtain a dry powder, which is monodisperse cadmium phosphide semiconductor nanoparticles.

[0052] The size of the monodisperse cadmium phosphide semiconductor nanoparticles was measured to be 3.5 nm, and they still exhibited high catalytic efficiency for tetracycline when used as a photocatalyst.

[0053] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing monodisperse cadmium phosphide semiconductor nanoparticles with freely adjustable size, characterized in that, Using cadmium oxide and oleic acid as raw materials, and octadecene as a medium, trimethylsilphosphine was added for phosphating reduction treatment under controlled reaction temperature to obtain a monodisperse cadmium phosphide particle with freely adjustable size. This particle is used for the catalytic degradation of tetracycline in dye wastewater, and the preparation steps are as follows: Accurately weigh cadmium oxide, oleic acid, and octadecene at a mass ratio of (1.4~1.5):1:(200~400), mix them evenly in a three-necked flask, start stirring, and then introduce argon gas into the three-necked flask as a protective gas to eliminate interference from oxidizing gases. Next, seal the three-necked flask, heat it to 250°C, and inject trimethylsilphosphine into the reaction solution at this temperature. The mass ratio of trimethylsilphosphine to cadmium oxide is controlled at (2~1):1, and this temperature is maintained for 10 min. Cool the three-necked flask to room temperature, pour out the solid-liquid reaction product from the flask, centrifuge, wash with chloroform and cyclohexane successively, and finally dry the powder to obtain monodisperse cadmium phosphide semiconductor nanoparticles.

2. The method for preparing monodisperse cadmium phosphide semiconductor nanoparticles with freely adjustable size according to claim 1, characterized in that, Prepare according to the following steps: Accurately weigh 0.7g of cadmium oxide, 0.48g of oleic acid, and 144g of octadecene into a three-necked flask, mix thoroughly, and start stirring; then, Argon gas was introduced into the three-necked flask as a protective gas to eliminate interfering gases inside the flask; then... Seal the three-necked flask, heat it to 250°C and maintain that temperature; then... 1.4 g of trimethylsilphosphine was injected into the reaction solution and kept at this temperature for 10 min; Cool the three-necked flask to room temperature naturally, and pour out the solid-liquid reaction products from the flask. Centrifugation was performed, followed by washing with chloroform and cyclohexane, and finally drying at 60°C for 8 hours to obtain a dry powder, which is monodisperse cadmium phosphide semiconductor nanoparticles.

3. The method for preparing monodisperse cadmium phosphide semiconductor nanoparticles with freely adjustable size according to claim 1, characterized in that, Prepare according to the following steps: Accurately weigh 0.7g of cadmium oxide, 0.48g of oleic acid, and 144g of octadecene into a three-necked flask, mix thoroughly, and start stirring; then, Argon gas was introduced into the three-necked flask as a protective gas to eliminate interfering gases inside the flask; then Seal the three-necked flask, heat it to 250°C and maintain that temperature; then... 0.7 g of trimethylsilphosphine was injected into the reaction solution and kept at this temperature for 10 min; Cool the three-necked flask to room temperature naturally, and pour out the solid-liquid reaction products from the flask. Centrifugation was performed, followed by washing with chloroform and cyclohexane, and finally drying at 60 °C for 8 h to obtain a dry powder, which is monodisperse cadmium phosphide semiconductor nanoparticles.

4. The method for preparing monodisperse cadmium phosphide semiconductor nanoparticles with freely adjustable size according to claim 1, characterized in that, Prepare according to the following steps: Accurately weigh 0.7g of cadmium oxide, 0.48g of oleic acid, and 144g of octadecene into a three-necked flask, mix thoroughly, and start stirring; then... Argon gas was introduced into the three-necked flask as a protective gas to eliminate interfering gases inside the flask; then Seal the three-necked flask, heat it to 250°C and maintain that temperature; then... 1.0 g of trimethylsilphosphine was injected into the reaction solution and kept at this temperature for 10 min; Cool the three-necked flask to room temperature naturally, and pour out the solid-liquid reaction products from the flask. Centrifugation was performed, followed by washing with chloroform and cyclohexane, and finally drying at 60 °C for 8 h to obtain a dry powder, which is monodisperse cadmium phosphide semiconductor nanoparticles.

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